Half adder (CLI args)

main.c

#include <stdio.h>
#include <stdlib.h>
#include "./utils.h"

int main(int argc, char** argv) {
		if (argc != 3) {
				fprintf(stderr, "Error: expected 2 args (numbers)\n");
				exit(EXIT_FAILURE);
		}

		/* for each arg */
		for (char** arg = argv + 1; arg < argv + 3; arg++) {
				/* for each arg char */
				for (char* c = *arg; *c != '\0'; c++) {
						if (!(*c == '0' || *c == '1')) {
								fprintf(stderr, "Error: invalid input: not integers 0 or 1\n");
								exit(EXIT_FAILURE);
						}
				}
		}

		struct Inputs inputs = {
				.a = strtol(argv[1], NULL, 10),
				.b = strtol(argv[2], NULL, 10)
		};

		struct Calculator calculator = {
				.sum = inputs.a ^ inputs.b,
				.carry = inputs.a && inputs.b,
		};

		printf("Sum: %d,\nCarry: %d\n", calculator.sum, calculator.carry);

		return EXIT_SUCCESS;
}

utils.h

#ifndef INPUTS_H
#define INPUTS_H

struct Inputs {
		int a;
		int b;
};

struct Calculator {
		int sum;
		int carry;
};

#endif // !INPUTS_H